1. Field of the Invention
The present invention relates to a small form-factor pluggable (SFP) optic transceiver module for fiber channel applications and, more particularly, to an optical transceiver module cage of high data transfer rate program GBIC.
2. The Related Art
Transceiver modules provide bidirectional transmission of data between an electrical interface and an optical data link. The module receives and converts electrically encoded data signals into optical signals which are then transmitted over the optical data link. Likewise, the module receives and converts optically encoded data signals into electrical signals and transmits the electrical signal in the electrical interface.
Normally, the transceiver module is mounted on a printed circuit board (PCB) assembly of a host computer, an input/output system, a peripheral device, or a switch. A small form-factor pluggable module connects with a metal cage assembly mounted on the PCB. The metal cage allows both ease of interconnection and ease of installation on PCB. The cage functions to dissipate electrostatics and serves as an electromagnetic shield.
The metal cage generally has two parallel sidewalls, a rectangular top, a rectangular bottom, and opposite ends. A conventional cage employs a two piece design. The two piece cage does not process a sufficient mechanical strength. Furthermore, the two piece design makes it difficult to manufacture and install the cage. In addition, the prior art cage forms legs for supporting the cage. However, no board locking mechanism is provided so that during the course of reflowing of a soldering process, the cage may inadvertently disengage from a PCB, causing poor soldering result.
To solve the problems of the prior art, the present invention provides a small form-factor pluggable metal cage employing a one-piece design and the cage of the present invention has two types of legs. The first type is compliant legs that can be assembled through a board. The second type is piggy legs which does not go through the board.
Accordingly, an object of the present invention is to provide a small form-factor pluggable metal cage having compliant legs, each defining an arc portion for preventing the cage from disengaging from a printed circuit board during the course of reflowing.
It is further object of the present invention is to provide a small form-factor pluggable metal cage that enhances assembly.
It is another object of the present invention to provide a metal cage of an optical transceiver having a one-piece structure which provides excellent mechanical stability.
It is still another object of the present invention to provide a metal cage structure of a small form-factor pluggable which enhances automated production and thus reduces costs of production.
Other objects, advantages and novel features of the present invention will be apparent from the following detailed description of preferred embodiments thereof with reference to the attached drawings, in which: